/Engine/Source/Runtime/Experimental/Iris/Core/Public/Iris/Serialization/NetBitStreamWriter.h
The returned BitStreamWriter will have similar behavior to a newly constructed regularFNetBitStreamWriter.
A BitStreamWriter that can be written to just like a regular BitStreamWriter.
[FNetBitStreamWriter](API\Runtime\IrisCore\Iris\Serialization\FNetBitStreamWriter) CreateSubstream ( uint32 MaxBitCount )